1.3. Operational mode

This chapter lists the available features for the epc600-device.

The range-finder works in combination with a tiny microprocessor. It operates according to a single shot principle. A command sent by the

microprocessor sets the user parameters in the chip and stimulates either a distance or ambient-light measurement. The device executes

the requested task standalone and sends back the answer (data) according to Figure 12.

Response:

Read data

Calculation n-1

Distances & Quality

Measurement n-1

Command:

Set parameters

Trigger capture

Response:

Read data

Calculation n

Distances & Quality

Measurement n

Command:

Set parameters

Trigger capture

Response:

Read data

Measurement n+1

Command:

Set parameters

Trigger capture

communication and data processing time

Measure n

Measure n-1

Measure n+1

Figure 12: Basic measurement cycle e.g. distance (or ambient-light)

The microprocessor controls the parameter settings for the measurement and the start. It computes from the read-out data the final dis-

tance. This also includes applying the necessary correction algorithms based on quality, ambient-light and temperature data and to adapt

the epc600 settings to the useful operational range and present scenery conditions.

The epc600 chip supports range finding as a single spot distance measurement, ambient-light measurement (similar to an optical pow -

er-meter or “Luxmeter”) and temperature metering.

1.3.1. Distance measurement

The distance measurement is done by single shots following the protocol in Figure 13, first section.

Request measurement:

- Select type

- Select integration time

- Send command

Wait for response

Read measurement data

Set measurement type

Set integration time

Do measurement

Send data

Idle

Idle

Calculate result

Request data:

- Send command

Tx

Wait for response

Read measurement data

Fetch data

Send data

Rx

Idle

Idle

epc600

Microprocessor

2-wire interface

Tx

Rx

Command:

1a) Measurement of distance

2a) Measurement of ambient-light

Response:

1b) Distance

2b) Ambient-light

Command:

3a) Read pixel status

4a) Read Q-subsample QSx

5a) Read temperature

Response:

3b) Valid & saturated pixels

4b) Q-subsample QSx

5b) Temperature

Figure 13: 2-wire communication sequences:

measurement (above) and data reading (below)

© 2014 ESPROS Photonics Corporation

Characteristics subject to change without notice

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Datasheet epc600 - V1.3

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